Alpha Alpha CB Boiler User manual

Installation Instructions
KIT CONTENTS
(The flue terminal is supplied with the boiler)
1. GENERAL
a. The flue system must be installed in accordance with BS 5440:1;1990.
b. The boiler must be installed in accordance with the Installation instructions supplied with the boiler.
c. The flue assembly supplied for the boiler is effectively 0.75 m in length for the 750 mm extension and 1.0 m for the
1000 mm extension.
Note: Additional flues (of the same length) are available to extend the flue up to a maximum equivalent flue length of 4 m, or
3 metre when fitted to an Alpha C23/27.
d. For vertical flue applications refer to separate instructions.
e. For horizontal flue applications ensure that there is a slight downward slope towards the terminal.
f. Use the following methods to determine the correct length of horizontal flue required:-
For rear exit flue L = B + 175 mm
For side exit flue L = B + C + 185 mm (min. side clearance required is 5 mm)
Where L = Required length of flue
B = Finished wall thickness
C = Distance from inside wall to the side of the boiler
g. Note: For rear or side flue, cut a 110 mm diameter hole (or use a 107 mm core drill) in the wall for the flue assembly.
h. Refer to the flue options and ensure the flue length does not exceed the maximum equivalent length of 4 metre, or
3 metre when fitted to an Alpha C23/27.
Fig. 1 - Horizontal side flue options
L = B + C + E + 185 mm
L = B + C + 185 mm
CB
E
CB
Front
Front
Lmax = equivalent flue length of 4 m (except C23/27, Lmax = 3 m)
Alpha CB/C/SY Boiler
750 and 1000 mm Flue Extensions
Concentric (60/100) Flue System
Kit Part No. 6.1000320 - 750 mm extension
Kit Part No. 6.1000322 - 1000 mm extension

04/04/D131
Part No. 6.9174342
Fig. 3 - Side flue
2. CUTTING THE FLUE DUCTS TO LENGTH
Refer to the Installation and Servicing instructions supplied with the boiler.
The following procedure applies to both rear or side exit flue. The only difference being the lengths to which the ducts are cut.
Rear flue Outer air duct length = finished wall thickness + 135 mm
Inner flue duct length = finished wall thickness + 172 mm
Side flue Outer air duct length = finished wall thickness + the distance from the inside wall to the side of the
boiler + 145 mm
Inner flue duct length = finished wall thickness + the distance from the inside wall to the side of the
boiler + 182 mm
If the overall length of the inner duct is greater than 790 or 1040 mm, then another flue extension is required.
Note: When cutting the flue ducts ensure that all cuts are square and burr free.
Note: If flue is more
than 1.5 m, the
restrictor must be
removed.
Fig. 2 - Rear flue
Compiled and designed by Publications 2000, Tel [phone]
These guidelines have been carefully prepared but we reserve the right to
alter the specification at any time in the interest of product improvement.
© Alpha Therm Limited 2004.
Alpha Therm Limited.
Nepicar House,LondonRoad, Wrotham Heath,
Sevenoaks, Kent TN15 7RS
Technical Helpline: 0870 3001 964
email: [e-mail]
website: www.alpha-innovation.co.uk